Tractable and reliable dynamic descriptions of cellular function at the metabolic level are becoming increasingly important to effectively utilize the extensive existing knowledge of metabolism for practical applications. A modeling effort is proposed herein to characterize the dynamics and control of metabolic activity in the mammalian red cell, with particular emphasis on the response of the glucose consuming pathways to changes in demand for ATP, NADH, NADPH, and 2, 3DPG. The heart of the program will be development of a dynamic metabolic model, by incorporating existing experimental data and enzyme kinetics into a mathematical framework we have developed. The model will contain a detailed description of the glucose metabolizing pathways, which are both the best understood and most important of pertinent reaction sequences from a dynamic modeling standpoint. We will probe the utility of this model: 1. for providing new and useful insight into the control strategy used by the red cell to meet conflicting demands under normal (basic physiology) and pathological situations, 2. to investigate the effects of common inborn errors in metabolism (enzyme deficiencies/defects) and how they affect the reaction to environmental stress (metabolic disorders), 3. to explore the utility of the metabolic model as a diagnostic tool (clinical applications), and 4. to use it as a basis to design on-line feedback control system to improve blood storage.